I'm a learner of Akka Streams in Scala. While I was reading at the IncomingConnection, I found Flow#join. Then, I found the following image on the comment of Flow#join.
+------+ +-------+
| | ~Out~> | |
| this | | other |
| | <~In~ | |
+------+ +-------+
But, I'm wondering what its structure is. I think the "join" makes a loop.
So I would like you to explain what structure "join" makes, and tell me simple sample code using Flow#join